Perhaps you should try some spelling variations:
significantly improve » significantly improved (Expand Search)
significantly better » significantly greater (Expand Search), significantly higher (Expand Search), significantly lower (Expand Search)
improve decrease » improve disease (Expand Search), improved urease (Expand Search), improves disease (Expand Search)
better decrease » greater decrease (Expand Search), teer decrease (Expand Search), between decreased (Expand Search)

You may be able to get more results by adjusting your search query.

• Removing quotes may allow a broader search: (( significantly better decrease ) OR ( significantly improve decrease )).